As with [1]} or [2]}, we assess the measures' performance by comparing their predictions in a corpus against a gold standard. Our gold standard is the rank of target words in Table REF  obtained by annotation. We obtain the measures' predictions for the target words by first calculating their values in a time period 1 before the starting point of change and in a time period 2 after that. We then compute the difference \(d\)  in values between period 1 and 2 for each target word and further rank the target words according to \(d\) . Next, we compute the rank correlation between each of these predicted ranks and the gold rank as a performance measure.
